[2B12-14] Aqueous Separation

[2B14] Extraction Properties of Acidic Diamide-type Extractant toward Minor Actinides and Rare Earth Elements

*Satoshi Nakamura¹, Hideya Suzuki¹, Sho Ishii¹, Tatsuya Emori¹, Tatsuya Kurosawa¹, Mitsunobu Shibata¹, Kojiro Shimojo¹, Yasutoshi Ban¹ (1. JAEA)

Keywords:Solvent extraction, minor actinide, americium, curium, B-TONAADA, partitioning and transmutation, SELECT process, MA separation

To reduce volume and radiotoxicity of high-level radioactive waste, JAEA has been developing a separation process called “SELECT” (Solvent Extraction from Liquid-waste using Extractants of CHON-type for Transmutation) for recovering minor actinides (MA) from high-level radioactive liquid-waste. In this study, the applicability of an acidic diamide-type extractant Branched-TetraOctylNitriloAceticAcidDiAmide (B-TONAADA) was investigated with a view to improving the efficiency of MA/Rare Earth Elements (RE) separation in SELECT process. As a results of extraction tests performed with different nitric acid concentrations, specific changes were observed in the lanthanide patterns of distribution ratios, and the distribution ratios of MA were higher than those of RE over a wide range of nitric acid concentrations.